I haven't seen any numbers on this, so this is just a hunch here -- but I think the biggest story behind this election is going to be the number of military votes the GOP lost (either to their Democrat opponents, or to apathy) in this election cycle. In fact, I would not be surprised if military votes ended up being the decisive factor in George Allen's loss to James Webb in Virginia.
I certainly agree that was the case in VA. Webb was an USNA grad, former Marine, a legitimate war hero [winner of the Navy Cross], former SecNav under Reagan, and had a son who is a Marine stationed in Iraq. Thanks to Webb's resume, Allen did not win enough votes in Norfolk and Virginia Beach to offset Webb's Northern VA margin of victory. But Webb is not your typical Dem candidate.
There also may be greater unhappiness with the war by the military and their families, especially in the National Guard. They are getting weary of the war in Iraq and the sacrifices they are making, especially with the additional demonization of the war by the cut and run Dems. Who wants to die for a mistake?